import random
ls1 = "abcdefghijklmnopqrstuvwxyz"
for i in range(100):
    num = "{:0>6}".format(i)
    word = ''.join(random.choices(ls1, k = 10))
    res = "{}.{}".format(num, word)
    print(res)
# 没有问题，不过还有别的写法